The implications of the Swiss result for Britain, which has had the mostBSE, are complex. Only cattle aged 30 months or younger are eaten inBritain, on the assumption, based on feeding trials, that cattle of thatage, even if they were infected as calves, have not yet accumulatedenough prions to be infectious. But the youngest cow to develop BSE onrecord in Britain was 20 months old, showing some are fast incubators.Models predict that 200-300 cattle under 30 months per year are infectedwith BSE and enter the food chain currently in Britain. Of these 3-5could be fast incubators and carrying detectable quantities of prion.

http://www.sare.org/htdocs/hypermail/html-home/28-html/0359.html

snip...

Commentary by European Microbiologist Roland Heynkes

August 26, 2003 Posted to BSE-L@UNI-KARLSRUHE.DE

> SECRETARY VENEMAN: "Well, thank you, Tony, for your question. As> you know, we've spent a considerable amount of time on this issue> of Canada and the single case of BSE. The announcement we made on> the 8th had several aspects. One was we were going to use a permit> process to open the border with respect to boxed beef from animals> under 30 months. As you know, animals under 30 months are generally> thought to be of virtually no risk of having BSE. Now, we will also> begin a regulatory process to look at the lowest risk animals,> those under 30 months. That regulation is in process at this point,> but it will take some time to actually do the regulation. That will> include a risk assessment and so forth.>

in my opinion this is a statement with intent to deceive and it is notcorrect. There have been several cases of clinical BSE in British cattleunder 30 months and it is therefore hardly possible to think that cattleunder 30 months have virtually no risk of having BSE. In 1988 theyoungest British BSE case was 24, the second youngest 27 months old. In1989 the youngest British BSE case was 21 and there were 4 cases only 24months old. In 1990 there were two cases only 24 and one 26 months old.In 1991 the youngest British BSE case was 24 and there were 3 cases only26 months old. In 1992 the youngest British BSE case was 20!, the secondyoungest 26 months old. In 1993 there was was a 29 months old case, in1995 the UK had a 24 months old case and in 1996 one British BSE casewas 29 months old.

http://www.defra.gov.uk/animalh/bse/bse-statistics/bse/yng-old.html

But mainly this wrong statement is misleading, because not theclinically sick cows are the problem for consumers. The real problem arethose animals that became infected as calves and are still incubatingthe infectivity during the incubation time of 5-6 years. For consumersit is therefore totally irrelevant that cattle are at low risk to reachthe clinical stage before being 30 months old. Important for consumersis the fact that most British BSE cases became infected as calves(http://www.heynkes.de/peaks.htm) and that infected calves are alreadyamplifying the infectivity. The advantage of young calves for consumersis that the infectivity in infected animals is low and stillconcentrated around the gastro- intestinal tract. But this is notnecessarily true for bulls, which are usually slaughtered when they are19-22 months old. They are too young to give positive results in theactual BSE tests, but they might be infective for consumers.

For US consumers it is of no importance whether a BSE-infected Canadiancow will show the first symptoms before or after it becomes 30 monthsold. Interesting for the consumers is only

1) if cattle are infected or not,

2) where in the animal is how much of the infectivity and

3) what happens to the infectivity during slaughtering?

If the US government is really interested to reduce consumers risk, ithas to

1) stop cannibalism among farm animals (no farm animal protein and fatin feeding stuff for farm animals, no possibility of cross contaminationof concentrate feed in mills and no lambing on pastures where scrapiemight be a problem)

2) test slaughter cattle above 24 months for BSE,

3) avoid contamination of the beef with prions from CNS by changingslaughter methods (electrical stunning instead of captive bolt, noimmobilisation with a pithing rod, no spreading of infectivity by sawingthrough the spinal cord),

5) commit the whole chain from abattoir to counter in shop andrestaurant to label products from cattle and sheep, because it is only amyth that scrapie is less infective than BSE.

In addition the US government should test all cattle and sheep whichdied or had to be killed because of illness. This measure should be holdout for at least one year in order to see the real BSE- andscrapie-incidence in the USA....